Use of supported rhodium catalysts in the preparation of tertiary butyl alcohol from tertiary butyl hydroperoxide

ABSTRACT

A method for preparing tertiary butyl alcohol wherein a feedstock comprising a solvent solution of tertiary butyl hydroperoxide in tertiary butyl alcohol or a mixture of tertiary butyl alcohol with isobutane is charged to a hydroperoxide decomposition reaction zone containing a catalytically effective amount of a hydroperoxide decomposition catalyst consisting essentially of alumina or carbon having rhodium deposited thereon and is brought into contact with the catalyst in liquid phase under hydroperoxide decomposition reaction conditions to convert the tertiary butyl hydroperoxide to decomposition products, principally tertiary butyl alcohol.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the catalytic decomposition of tertiary butylhydroperoxide (TBHP). More particularly, this invention relates to amethod for the preparation of tertiary butyl alcohol (TBA) by thecatalytic decomposition of tertiary butyl hydroperoxide. Still moreparticularly, this invention relates to a method wherein an alumina orcarbon supported rhodium catalyst is used to catalyze the substantiallyselective decomposition of tertiary butyl hydroperoxide to tertiarybutyl alcohol.

2. Prior Art

It is known to react isobutane with oxygen, either thermally orcatalytically, to form a peroxidation reaction product wherein theprincipal peroxide that is formed is tertiary butyl hydroperoxide. It isalso known to thermally or catalytically decompose the tertiary butylhydroperoxide to form tertiary butyl alcohol.

In the text entitled "Organic Peroxides" edited by Daniel Swern (WileyInterscience, a Division of John Wiley & Sons, New York), in Vol. II onpage 157 it is stated that the metal-ion-catalyzed decomposition ofprimary hydroperoxides yields mainly alcohols, aldehydes and carboxylicacids, citing as an example the decomposition of hydroxymethylhydroperoxide with aqueous ferrous sulfate to provide formaldehyde,formic acid and water.

Quin U.S. Pat. No. 2,854,487 discloses the hydrogenation of hydrocarbonperoxides in the presence of hydrogen and palladium on activated aluminato provide carbinols.

In Massie U.S. Pat. No. 3,775,472 a process is disclosed wherein alkylsubstituted aromatic hydrocarbons are oxidized to products such asaromatic alcohols, aldehydes and carboxylic acids in the presence ofruthenium compounds.

Grane U.S. Pat. No. 3,474,151 discloses that tertiary butyl alcoholstarts to dehydrate at 450° F. and to decompose at a "rapid rate" attemperatures above 475° F. Grane discovered, however, that residualquantities of hydroperoxide contaminants present in tertiary butylalcohol could be thermally decomposed by heating the contaminatedtertiary butyl alcohol at a temperature of 375° to 475° F. for about 1to 10 minutes.

Grane et al. U.S. Pat. No. 4,294,999 discloses a process whereinisobutane is oxidized in a pressured reactor in the presence of asolubilized molybdenum catalyst to provide a mixture of tertiary butylalcohol, tertiary butyl hydroperoxide, methanol, acetone, and otheroxygen-containing compounds. The tertiary butyl hydroperoxide isthermally decomposed under pressure at about 280° F. to provide atertiary butyl alcohol product containing only residual quantities oftertiary butyl hydroperoxide which are then decomposed in accordancewith Grane U.S. Pat. No. 3,474,151 by heating the tertiary butyl alcoholat 375° to 475° for about 1 to 10 minutes. Heating tertiary butylalcohol containing small amounts of peroxides at high temperatures foreven short periods of time to remove the peroxides produces undesirableproducts such as isobutylene.

Grane et al. U.S. Pat. No. 4,296,262 discloses a related process whereinisobutane is reacted with oxygen in a reaction zone for a residence timeof about 1 to 10 hours at a temperature of about 240° to about 340° F.and a pressure of about 100 to about 1000 psig. in the presence of acatalytically effective amount of a soluble molybdenum catalyst. Aliquid stream comprising tertiary butyl alcohol is recovered from thereaction mixture and fed to a decomposition zone wherein the tertiarybutyl hydroperoxide contained therein is decomposed by "hot aging" at250°-350° F. at a pressure lower than the pressure in the oxidationzone. The tertiary butyl alcohol can be further subjected to a clean-uptreatment at 375°-475° F. for 1 to 10 minutes. Worrell et al. in U.S.Pat. No. 4,296,263 disclose a related process wherein the feedstock is amixture of normal butane with isobutane and wherein the oxidationcatalyst is a soluble form of chromium, cobalt, nickel, manganese,molybdenum, or a mixture thereof.

In U.S. Pat. No. 3,505,360, Allison et al. disclose a method wherein analkenyl hydroperoxide is decomposed in the presence of a catalyst basedon a compound of a Group IV-A, V-A or VI-A metal. Taylor et al., in U.S.Pat. No. 4,508,923 disclose the use of a catalyst system comprisingruthenium and chromium for decomposing organic hydroperoxides. The useof a cobalt borate catalyst for the decomposition of hydroperoxides isdisclosed in Sanderson et al. U.S. Pat. No. 4,547,598.

Taylor et al. U.S. Pat. No. 4,551,553 is directed to a process for theformation of alcohols such as tertiary butyl alcohol by the catalyticdecomposition of an organic hydroperoxide such as tertiary butylhydroperoxide using a binary catalyst composed of a mixture of aruthenium compound with a chromium compound. It is stated that the useof the binary catalyst eliminates the need for stabilizing ligands.

Sanderson et al. disclose the use of a variety of catalysts for thedecomposition of tertiary butyl hydroperoxide in a series of U.S.patents, including a catalyst composed of unsupported nickel, copper,chromia and iron (U.S. Pat. No. 4,704,482), a catalyst composed of iron,copper, chromia and cobalt (U.S. Pat. No. 4,705,903), a catalystcomposed of a base treated hydrogenation catalyst from groups VIB orVIIIB of the Periodic Table (U.S. Pat. No. 4,742,179), a catalystconsisting essentially of nickel, copper, chromium and barium (U.S. Pat.No. 4,873,380), a catalyst composed of a metal phthalocyanine promotedwith a rhenium compound (U.S. Pat. No. 4,910,349), a catalyst composedof a base promoted metal phthalocyanine compound (U.S. Pat. No.4,912,269), a catalyst composed of a soluble ruthenium compound promotedwith a bidentate ligand (U.S. Pat. No. 4,912,033), a catalyst composedof a metal porphine such as iron (III) or manganese (III) promoted withan alkyl thiol or an amine, a catalyst composed of an imidazole promotedmetal phthalocyanine compound (U.S. Pat. No. 4,912,266), (U.S. Pat. No.4,922,034), a catalyst composed of a metal phthalocyanine promoted witha thiol and a free radical inhibitor (U.S. Pat. No. 4,922,035), acatalyst composed of a borate promoted metal phthalocyanine (U.S. Pat.No. 4,922,036), or a catalyst composed of a soluble ruthenium compoundand an iron compound such as an acetate, a borate, a bromide, achloride, a 1,3-propanedionate, a 2-ethyl-hexanoate, an iodide, anitrate, a 2,4-pentanedionate, a perchlorate or a sulfate (U.S. Pat. No.5,025,113).

BACKGROUND INFORMATION

When isobutane is reacted with molecular oxygen, the principal productsof the reaction are tertiary butyl alcohol and tertiary butylhydroperoxide. However, minor amounts of other contaminants are alsoformed.

In addition, a minor amount of water will be formed, which will normallyamount to about 0.5 to 1 wt. % of the reactor effluent. The Mount ofbyproduct water that is produced is a function of the severity of thereaction conditions employed and will tend to increase as the severityof the reaction conditions is increased.

As indicated, tertiary butyl hydroperoxide is useful as a raw materialfor the manufacture of tertiary butyl alcohol. The tertiary butylalcohol can be formed by catalytic decomposition of the tertiary butylhydroperoxide. In the Williams et al. process disclosed in U.S. Pat. No.3,472,876, an oxygen-containing gas was charged to a reactor containingisobutane and an oxidation catalyst to provide a reaction mixturecomprising tertiary butyl alcohol, tertiary butyl hydroperoxide,acetone, and tertiary butyl ether. The reported results in the patentindicate that there was a comparatively low rate of conversion and acomparatively poor selectivity of the reaction to tertiary butylalcohol.

SUMMARY OF THE INVENTION

In accordance with the present invention, a solvent solution of atertiary butyl hydroperoxide charge stock is brought into contact with acatalytically effective amount of a hydroperoxide decomposition catalystin a hydroperoxide decomposition reaction zone in liquid phase withagitation to convert the tertiary butyl hydroperoxide to decompositionproducts, principally tertiary butyl alcohol, the hydroperoxidedecomposition catalyst being a supported hydroperoxide decompositioncatalyst consisting essentially of alumina or carbon having depositedthereon from about 0.01 to about 1 wt. % of rhodium and tertiary butylalcohol is recovered from the products of the hydroperoxidedecomposition reaction.

DESCRIPTION OF THE PROCESS OF THE PRESENT INVENTION

The starting materials for the process of the present invention are atertiary butyl hydroperoxide feedstock and a supported rhodium catalyst.

The Tertiary Butyl Hydroperoxide Feedstock

The tertiary butyl hydroperoxide charge stock may comprise an isobutaneoxidation product wherein the tertiary butyl hydroperoxide is dissolvedin a mixture of isobutane and tertiary butyl alcohol or may comprise anisobutane oxidation product enriched by the addition of tertiary butylalcohol, such that the solution of tertiary butyl alcohol in the mixtureof isobutane with tertiary butyl alcohol contains from about 5 to about30 wt. % of tertiary butyl hydroperoxide.

Alternately, the isobutane reaction product may be charged to adistillation zone where unreacted isobutane is removed as a distillatefraction for recycle to thereby provide a solution of tertiary butylhydroperoxide in tertiary butyl alcohol containing about 5 to about 30wt. % of tertiary butyl hydroperoxide.

The Catalyst System

The hydroperoxide decomposition catalyst to be used in accordance withthe present invention is a supported hydroperoxide decompositioncatalyst consisting essentially of alumina or carbon having depositedthereon from about 0.01 to about 1 wt. % of rhodium.

Catalytic Decomposition of Tertiary Butyl Hydroperoxide

The process of the present invention may be conducted batchwise inkettles or by continuously passing the reactants through a tubularreactor.

The catalytic decomposition of the tertiary butyl hydroperoxide ispreferably conducted at a temperature within the range of about 20° toabout 160° C. and, more preferably, at a temperature within the range ofabout 80° to about 100° C. The reaction is preferably conducted at apressure sufficient to keep the reactants and the reaction products inliquid phase. A pressure of about 0 to about 10,000 psig. may be used,if desired.

Flow rates of the charge solution to the reaction zone should beadjusted in order to provide an appropriate contact time within thereactor. In a batch process, the holding time may suitably be from about0.5 to about 10 hours, and more preferably about 1 to 3 hours.

In accordance with the most preferred embodiment of the presentinvention, isobutane is reacted with oxygen in an oxidation zone underoxidation reaction conditions including a temperature of about 135° toabout 155° C., a pressure of about 300 to about 800 psig., and a holdingtime of about 2 to about 6 hours to provide an initial oxidationreaction product comprising unreacted isobutane, tertiary butylhydroperoxide, tertiary butyl alcohol, and oxygen-containingby-products. The initial oxidation reaction product is then used as thetertiary butyl hydroperoxide charge stock of the present invention. Ifthe concentration of tertiary butyl hydroperoxide in the tertiary butylhydroperoxide charge stock is more than about 30 wt. % of the initialoxidation reaction product, the initial oxidation reaction product canbe diluted with an amount of tertiary butyl alcohol sufficient to lowerthe concentration of the tertiary butyl hydroperoxide to a desiredpercentage, to provide, for example, a tertiary butyl hydroperoxidecharge stock containing from about 15 to about 25 wt. % of tertiarybutyl hydroperoxide.

Alternately, the initial oxidation reaction product may be fractionatedin any appropriate manner (e.g., by distillation in a distillation zone)to remove the isobutane therefrom for recycle and to provide a solutionof tertiary butyl hydroperoxide and tertiary butyl alcohol which willnormally contain from about 5 to about 30 wt. % of tertiary butylhydroperoxide.

The solution of tertiary butyl hydroperoxide in tertiary butyl alcoholis then charged to a catalytic hydroperoxide decomposition zone where itis brought into contact with a carbon or alumina supported rhodiumcatalyst to substantially selectively convert the tertiary butylhydroperoxide to tertiary butyl alcohol with high yields andselectivities.

As indicated, the catalytic decomposition of the tertiary butylhydroperoxide in the catalytic hydroperoxide decomposition reaction zonemay suitably be conducted at a temperature within the range of about 20°to about 160° C., preferably from about 60° to about 120° C., and morepreferably from about 80° to 100° C. at autogenous pressure or ifdesired at a superatmospheric pressure up to 10,000 psig. for a contacttime within the range of about 0.5 to about 10 hours, and morepreferably about 1 to 3 hours.

When the process of the present invention is practiced in a continuousmanner by continuously charging the tertiary butyl hydroperoxide chargestock to a reactor containing a fixed bed of pelleted hydroperoxidedecomposition catalyst, the space velocity is suitably in the range ofabout 0.5 to about 3 volumes of tertiary butyl hydroperoxide chargestock per volume of catalyst per hour. Preferably, the space velocity iswithin the range of about 1 to about 2 volumes of tertiary butylhydroperoxide charge stock per volume of catalyst per hour.

The reaction product from the tertiary butyl hydroperoxide decompositionstep may then be fractionated in any suitable manner, such as bydistillation to recover the tertiary butyl alcohol.

SPECIFIC EXAMPLES

The invention will be further illustrated by the following specificexamples which are given by way of illustration and not as limitationson the scope of this invention.

Procedure

The reactor that was used for the experiments was a stainless steel tube(0.51"×29") which was electrically heated. Liquid feed was pumped intothe bottom of the reactor using a Ruska dual drive pump. Pressure wasregulated using a Skinner Uni-Flow valve and a Foxboro controller.Samples were collected at the top of the reactor, cooled to ambienttemperature, filtered and analyzed by GC. The analysis of the feed andof the products obtained is reported in the following tables.

                                      TABLE 1                                     __________________________________________________________________________    CATALYTIC CONVERSION OF TERT-BUTYLHYDROPEROXIDE                               TO TERT-BUTYLALCOHOL                                                          Notebook Number                                                                             6844-10-A                                                                           6906-25-1                                                                           6906-25-2                                                                           6906-25-3                                                                           6906-25-4                               __________________________________________________________________________    Catalyst            0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                     on Al.sub.2 O                                                                       on Al.sub.2 O.sub.3                                                                 on Al.sub.2 O.sub.3                                                                 on Al.sub.2 O.sub.3                     Catalyst (cc)       100   100   100   100                                     Pressure (psi)      500   500   500   500                                     Feed Rate (cc/Hr.)  50    50    50    50                                      Temperature (°C.)                                                                          80    100   120   140                                     Time on stream (Hr) 4     4     4     4                                       Space Vel. (cc/cc)  0.5   0.5   0.5   0.5                                     TBHP Conversion (mol. %)                                                                          100.0 98.4  99.8  99.9                                    Selectivity IC4 = (mol. %)                                                                        -0.0  0.0   0.0   0.0                                     Sel. Acetone (mol. %)                                                                             12.4  27.2  37.8  45.3                                    Sel. Methanol (mol. %)                                                                            2.0   5.7   6.9   8.4                                     Sel. TBA (mol. %)   81.5  69.7  61.2  54.3                                    Sel. DTBP (mol. %)  6.1   3.0   0.9   0.4                                     Remarks       H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                        Basis Basis Basis Basis Basis                                   Composition, wt %                                                             IC4 =         0.001 0.000 0.002 0.003 0.003                                   MEOH/MF       0.016 0.153 0.401 0.486 0.588                                   Acetone       0.008 1.540 3.314 4.665 5.590                                   TBA           79.968                                                                              95.506                                                                              94.616                                                                              92.984                                                                              92.409                                  DTBP          0.055 1.005 0.520 0.201 0.117                                   TBHP          19.146                                                                              0.000 0.305 0.042 0.016                                   __________________________________________________________________________

                                      TABLE 2                                     __________________________________________________________________________    CATALYTIC CONVERSION OF TERT-BUTYLHYDROPEROXIDE                               TO TERT-BUTYLALCOHOL                                                          Notebook Number                                                                             6844-10-A                                                                           6906-26-1                                                                           6906-26-2                                                                           6906-26-3                                                                           6906-26-4                               __________________________________________________________________________    Catalyst            0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                     on Al.sub.2 O.sub.3                                                                 on Al.sub.2 O.sub.3                                                                 on Al.sub.2 O.sub.3                                                                 on Al.sub.2 O.sub.3                     Catalyst (cc)       100   100   100   100                                     Pressure (psig)     500   500   500   500                                     Feed Rate (cc/Hr.)  100   100   100   100                                     Temperature (°C.)                                                                          80    100   120   140                                     Time on Stream (Hr) 4     4     4     4                                       Space Vel. (cc/cc)  1.0   1.0   1.0   1.0                                     TBHP Conversion (mol. %)                                                                          80.1  96.4  99.8  100.0                                   Selectivity IC4 = (mol. %)                                                                        0.0   -0.0  0.1   0.0                                     Sel. Acetone (mol. %)                                                                             11.9  23.2  37.6  33.6                                    Sel. Methanol (mol. %)                                                                            1.8   6.0   7.9   14.7                                    Sel. TBA (mol. %)   81.5  74.3  61.4  66.0                                    Sel. DTBP (mol. %)  6.6   2.5   1.0   0.3                                     Remarks       H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 Free                                                                        H.sub.2 O Free                                        Basis Basis Basis Basis Basis                                   Composition, wt %                                                             IC4 =         0.001 0.001 0.000 0.009 0.001                                   MEOH/MF       0.016 0.116 0.410 0.552 4.156                                   Acetone       0.008 1.187 2.770 4.632 4.156                                   TBA           79.968                                                                              91.659                                                                              93.584                                                                              93.180                                                                              93.599                                  DTBP          0.055 0.874 0.430 0.215 0.100                                   TBHP          19.146                                                                              3.808 0.685 0.039 0.000                                   __________________________________________________________________________

                                      TABLE 3                                     __________________________________________________________________________    CATALYTIC CONVERSION OF TERT-BUTYLHYDROPEROXIDE                               TO TERT-BUTYLALCOHOL                                                          Notebook Number                                                                             6844-10-A                                                                           6906-27-1                                                                           6906-27-2                                                                           6906-27-3                                                                           6906-27-4                               __________________________________________________________________________    Catalyst            0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                     on Al.sub.2 O.sub.3                                                                 on Al.sub.2 O.sub.3                                                                 on Al.sub.2 O.sub.3                                                                 on Al.sub.2 O.sub.3                     Catalyst (cc)       100   100   100   100                                     Pressure (psig)     500   500   500   500                                     Feed Rate (cc/Hr.)  200   200   200   200                                     Temperature (°C.)                                                                          80    100   120   140                                     Time on Stream (Hr) 4     4     4     4                                       Space Vel. (cc/cc)  2.0   2.0   2.0   2.0                                     TBHP Conversion (mol. %)                                                                          56.7  90.5  99.5  99.9                                    Selectivity IC4 = (mol. %)                                                                        0.0   -0.0  0.0   0.1                                     Sel. Acetone (mol. %)                                                                             10.6  19.1  39.8  51.3                                    Sel. Methanol (mol. %)                                                                            1.7   5.1   8.8   10.3                                    Sel. TBA (mol. %)   82.6  78.0  59.4  48.4                                    Sel. DTBP (mol. %)  6.8   3.0   0.8   0.2                                     Remarks       H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                        Basis Basis Basis Basis Basis                                   Composition, wt %                                                             IC4 =         0.001 0.001 0.000 0.005 0.007                                   MEOH/MF       0.016 0.082 0.328 0.609 0.717                                   Acetone       0.008 0.749 2.137 4.890 6.338                                   TBA           79.968                                                                              88.220                                                                              92.537                                                                              92.489                                                                              90.901                                  DTBP          0.055 0.652 0.470 0.181 0.090                                   TBHP          19.146                                                                              8.282 1.814 0.092 0.013                                   __________________________________________________________________________

                                      TABLE 4                                     __________________________________________________________________________    CATALYTIC CONVERSION OF TERT-BUTYLHYDROPEROXIDE                               TO TERT-BUTYLALCOHOL                                                          Notebook Number                                                                             6844-10-A                                                                           6906-31-1                                                                           6906-31-2                                                                           6906-31-3                                                                           6906-31-4                               __________________________________________________________________________    Catalyst            0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                     on C  on C  on C  on C                                    Catalyst (cc)       50    50    50    50                                      Pressure (psig)     500   500   500   500                                     Feed Rate (cc/Hr.)  25    25    25    25                                      Temperature (°C.)                                                                          80    100   120   140                                     Time on Stream (Hr) 4     4     4     4                                       Space Vel. (cc/cc)  0.5   0.5   0.5   0.5                                     TBHP Conversion (mol. %)                                                                          99.4  99.6  99.9  99.9                                    Selectivity IC4 = (mol. %)                                                                        0.0   0.1   0.7   39.7                                    Sel. Acetone (mol. %)                                                                             16.9  18.9  23.0  30.8                                    Sel. Methanol (mol. %)                                                                            1.3   1.8   3.4   4.4                                     Sel. TBA (mol. %)   72.3  72.7  70.3  69.0                                    Sel. DTBP (mol. %)  10.7  8.3   6.7   0.2                                     Remarks       H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                        Basis Basis Basis Basis Basis                                   Composition, wt %                                                             IC4 =         0.001  0.003                                                                              0.016 0.082 4.727                                   MEOH/MF       0.016 0.103 0.136 0.250 0.315                                   Acetone       0.008 2.084 2.335 2.839 3.804                                   TBA           79.968                                                                              94.320                                                                              94.507                                                                              94.269                                                                              89.139                                  DTBP          0.055 1.711 1.342 1.095 0.081                                   TBHP          19.146                                                                              0.114 0.079 0.024 0.012                                   __________________________________________________________________________

                                      TABLE 5                                     __________________________________________________________________________    CATALYTIC CONVERSION OF TERT-BUTYLHYDROPEROXIDE                               TO TERT-BUTYLALCOHOL                                                          Notebook Number                                                                             6844-10-A                                                                           6906-32-1                                                                           6906-32-2                                                                           6906-3-3                                                                            6906-32-4                               __________________________________________________________________________    Catalyst            0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                     on C  on C  on C  on C                                    Catalyst (cc)       50    50    50    50                                      Pressure (psig)     500   500   500   500                                     Feed Rate (cc/Hr.)  50    50    50    50                                      Temperature (°C.)                                                                          80    100   120   140                                     Time on Stream (Hr) 4     4     4     4                                       Space Vel. (cc/cc)  1.0   1.0   1.0   1.0                                     TBHP Conversion (mol. %)                                                                          99.4  99.4  99.8  100.0                                   Selectivity IC4 = (mol. %)                                                                        0.5   0.2   1.2   8.0                                     Sel. Acetone (mol. %)                                                                             20.2  22.9  26.8  32.8                                    Sel. Methanol (mol. %)                                                                            1.4   2.7   4.2   6.0                                     Sel. TBA (mol. %)   73.2  72.3  70.1  66.3                                    Sel. DTBP (mol. %)  6.6   4.8   3.2   0.9                                     Remarks       H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                        Basis Basis Basis Basis Basis                                   Composition, wt %                                                             IC4 =         0.001 0.063 0.023 0.146 0.957                                   MEOH/MF       0.016 0.110 0.197 0.301 0.425                                   Acetone       0.008 2.490 2.813 3.305 4.054                                   TBA           79.968                                                                              94.343                                                                              94.263                                                                              94.152                                                                              92.735                                  DTBP          0.055 1.075 0.793 0.544 0.193                                   TBHP          19.146                                                                              0.100 0.113 0.035 0.006                                   __________________________________________________________________________

                                      TABLE 6                                     __________________________________________________________________________    CATALYTIC CONVERSION OF TERT-BUTYLHYDROPEROXIDE                               TO TERT-BUTYLALCOHOL                                                          Notebook Number                                                                             6844-10-A                                                                           6906-33-1                                                                           6906-33-2                                                                           6906-33-3                                                                           6906-33-4                               __________________________________________________________________________    Catalyst            0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                                             0.5% Rh                                                     on C  on C  on C  on C                                    Catalyst (cc)       50    50    50    50                                      Pressure (psig)     500   500   500   500                                     Feed Rate (cc/Hr.)  100   100   100   100                                     Temperature (°C.)                                                                          80    100   120   140                                     Time on Stream (Hr) 4     4     4     4                                       Space Vel. (cc/cc)  2.0   2.0   2.0   2.0                                     TBHP Conversion (mol. %)                                                                          98.9  99.2  99.8  100.0                                   Selectivity IC4 = (mol. %)                                                                        0.1   0.1   0.0   0.3                                     Sel. Acetone (mol. %)                                                                             23.5  25.3  23.7  30.6                                    Sel. Methanol (mol. %)                                                                            2.5   3.8   4.5   6.9                                     Sel. TBA (mol. %)   70.6  70.5  73.4  68.4                                    Sel. DTBP (mol. %)  5.9   4.2   3.0   1.1                                     Remarks       H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                                                      H.sub.2 O Free                                        Basis Basis Basis Basis Basis                                   Composition, wt %                                                             IC4 =         0.001 0.018 0.009 0.003 0.039                                   MEOH/MF       0.016 0.186 0.273 0.319 0.483                                   Acetone       0.008 2.881 3.103 2.923 3.778                                   TBA           79.968                                                                              93.583                                                                              93.716                                                                              94.503                                                                              93.715                                  DTBP          0.055 0.959 0.709 0.513 0.221                                   TBHP          19.146                                                                              0.205 0.158 0.038 0.008                                   __________________________________________________________________________

A 19.1% solution of TBHP in TBA was converted over Rh/C or Rh/Al₂ O₃catalysts to TBA in good yields. For example, a 0.5% rhodium on aluminacatalyst (80° C., 0.5 space velocity) gave 100% TBHP conversion with thefollowing selectivities: TBA 81.5%, DTBP 6.1%, acetone 12.4%, methanol2.0%.

A Rh on carbon catalyst gave essentially the same results, i.e., almostcomplete conversion of the TBHP at 80° C.

Typical catalysts under these conditions give 80% or less conversion.Thus, Rh/Al₁ O₃ and Rh/C catalysts are among the most active catalystsfor the conversion of TBHP to TBA.

Having thus described our invention, what is claimed is:
 1. In a method wherein a solvent solution of a tertiary butyl hydroperoxide charge stock is brought into contact with a catalytically effective amount of a hydroperoxide decomposition catalyst in a hydroperoxide decomposition reaction zone in liquid phase with agitation to convert said tertiary butyl hydroperoxide to decomposition products, principally tertiary butyl alcohol, the improvement which comprises:a) using, as said hydroperoxide decomposition catalyst, a carbon or alumina supported hydroperoxide decomposition catalyst consisting essentially of rhodium, and b) recovering tertiary butyl alcohol from the products of said hydroperoxide decomposition reaction.
 2. A method as in claim 1 wherein the solvent comprises tertiary butyl alcohol.
 3. A method as in claim 1 wherein the solvent comprises a mixture of isobutane with tertiary butyl alcohol.
 4. A method as in claim 1 wherein the support consists of alumina.
 5. A method as in claim 1 wherein the support consists of carbon.
 6. In a method wherein a solution of a tertiary butyl hydroperoxide charge stock in tertiary butyl alcohol that contains from about 5 to about 30 wt. % of tertiary butyl hydroperoxide is brought into contact with a catalytically effective amount of a hydroperoxide decomposition catalyst in a hydroperoxide decomposition reaction zone in liquid phase with agitation under hydroperoxide conversion conditions including a temperature within the range of about 25° to about 250° C. and a pressure of about 0 to about 1,000 psig to convert said tertiary butyl hydroperoxide to decomposition products, principally tertiary butyl alcohol, the improvement which comprises:a) using, as said hydroperoxide decomposition catalyst, a catalyst consisting essentially of alumina or carbon having deposited from about 0.1 to about 1 wt. % of rhodium, and b) recovering tertiary butyl alcohol from the products of said hydroperoxide decomposition reaction.
 7. A method as in claim 6 wherein the temperature is in the range of about 40° to about 150° C. and the pressure is about 0 psig.
 8. A method as in claim 6 wherein the support consists of alumina.
 9. A method as in claim 6 wherein the support consists of carbon.
 10. In a method wherein a solution of a tertiary butyl hydroperoxide charge stock in a mixture of isobutane with tertiary butyl alcohol that contains from about 5 to about 30 wt. % of tertiary butyl hydroperoxide is brought into contact with a catalytically effective Mount of a hydroperoxide decomposition catalyst in a hydroperoxide decomposition reaction zone in liquid phase under hydroperoxide conversion conditions including a temperature within the range of about 25° to about 250° C. and a pressure of about 0 to about 10,000 psig to convert said tertiary butyl hydroperoxide to decomposition products, principally tertiary butyl alcohol, the improvement which comprises:a) using, as said hydroperoxide decomposition catalyst, a hydroperoxide decomposition catalyst consisting essentially of alumina or carbon having deposited thereon from about 0.1 to about 1 wt. % of a rhodium, and b) recovering tertiary butyl alcohol from the products of said hydroperoxide decomposition reaction.
 11. A method as in claim 10 wherein the temperature is in the range of about 40° to about 150° C. and the pressure is about 0 psig.
 12. A method as in claim 11 wherein the support consists of alumina.
 13. A method as in claim 11 wherein the support consists of carbon. 